Understanding the Challenges of Climate Change Adaptation in Water Management
As global temperatures rise and precipitation patterns become increasingly unpredictable, water infrastructure planning faces unprecedented challenges. Communities around the world must grapple with the uncertainty of future water availability, demand, and extreme weather events that could compromise their ability to reliably deliver safe, clean water to residents.
One such community is Mombasa, Kenya’s second-largest city, where water demand is expected to double by 2035 to an estimated 300,000 cubic meters per day. Mombasa’s current water supply comes primarily from substantial precipitation in the region, but climate change projections paint an unclear picture of whether rainfall levels will rise or fall in the coming decades. This uncertainty makes it extremely difficult to determine the appropriate size and capacity of a proposed dam and reservoir system along the Mwache River, which currently provides around 310,000 cubic meters per day.
“We found that the flexible adaptive option, which allows for the dam’s height to be increased incrementally, substantially reduces the risk of overbuilding infrastructure that you don’t need, and maintains a similar level of water supply reliability in comparison to having a larger dam from the get-go,” explains Sarah Fletcher, the lead author of a study published in the journal Nature Communications that explored this challenge.
Developing a New Planning Framework for Flexible Water Infrastructure
To help cities like Mombasa navigate the complexities of water infrastructure planning amidst climate change uncertainty, a team of researchers from the MIT Joint Program on the Science and Policy of Global Change has developed a systematic approach that assesses the potential to learn about regional climate change over time. This new framework enables decision-makers to evaluate whether adaptive, flexible approaches are likely to be more cost-effective and reliable than static, irreversible options.
The key insight of this framework is that climate model projections, while useful in establishing a range of potential trajectories, often assume that uncertainty about the magnitude and timing of climate changes will persist throughout the entire planning timeline, which can span multiple decades. By estimating how much planners can expect to learn about climate change in the future, the new framework can enable the evaluation of whether adaptive approaches are likely to be more suitable than static designs.
“Climate models can provide us with a useful range of potential trajectories of the climate system,” says Megan Lickley, a co-author of the study and a PhD student in the Department of Earth, Atmospheric and Planetary Sciences. “There is considerable uncertainty in terms of the magnitude and timing of these changes over the next 50 to 100 years. In this work, we show how to incorporate learning into these large infrastructure decisions as we gain new knowledge about the climate trajectory over the coming decades.”
Applying the Framework to the Mwache Dam Project
Using this planning framework, the research team analyzed the proposed Mwache Dam project in Mombasa, comparing the lifetime costs and water supply reliability of a flexible, adaptive approach with two static, irreversible options: one designed for the driest, warmest climate projection, and the other for the current climate.
The results showed that the flexible, adaptive approach, which allows for the dam’s height to be increased incrementally as new information becomes available, is the most cost-effective while still maintaining a reliable supply of water to Mombasa. This finding highlights the importance of incorporating the potential to learn about climate change over time into infrastructure decision-making, rather than assuming that today’s uncertainty will persist indefinitely.
“For example, if you started off on a high-temperature trajectory and 40 years from now you remain on that trajectory, you would know that none of the low-temperature design options are feasible anymore,” explains Sarah Fletcher. “At that point, you would have exceeded a certain amount of warming, and could then rule out the low-temperature-change planning option, and take advantage of an adaptive approach to increase the capacity.”
Implications for Sustainable Water Infrastructure Design
By identifying opportunities to reliably apply flexible, adaptive approaches to water infrastructure design, the new planning framework developed by the MIT researchers could lead to substantial savings in climate adaptation investments. These savings could then be directed towards providing water infrastructure solutions to many more resource-limited communities that face significant climate risks.
This study may be the first to address a critical limitation in traditional water infrastructure planning, which has often assumed that current climate change uncertainty estimates will persist throughout the entire planning timeline. By incorporating the potential for learning into the decision-making process, the new framework empowers city planners and water managers to make more informed, cost-effective, and reliable choices for their communities’ long-term water security.
As the Kenyan government finalizes the design of the Mwache Dam, the results from this study have already informed the ongoing planning and master planning process, demonstrating the real-world impact of cutting-edge climate research. By sharing these insights, the Joint Action for Water blog aims to inspire other communities grappling with the challenges of sustainable water infrastructure design in the face of a changing climate.
Adapting Water Infrastructure to Emerging Climate Risks
Beyond the specific case of the Mwache Dam, the planning framework developed by the MIT researchers offers a versatile approach that can be applied to a wide range of water infrastructure projects around the world. By considering the potential for learning about future climate conditions, decision-makers can make more informed choices about the most appropriate design approaches for their communities.
Some key strategies and considerations for adapting water infrastructure to emerging climate risks include:
Flexible and Incremental Approaches
: Designing water systems with the ability to scale up or add capacity over time, rather than investing in large, static infrastructure that may become oversized or obsolete as climate conditions change.
Scenario Planning and Sensitivity Analysis
: Evaluating a range of potential future climate scenarios, including both best-case and worst-case projections, to stress-test infrastructure plans and identify vulnerabilities.
Integrating Land Use and Water Resource Management
: Aligning water infrastructure planning with broader land use and development plans to ensure that growth and water demand can be sustainably supported.
Enhancing Resilience through Green Infrastructure
: Incorporating nature-based solutions, such as wetlands, permeable surfaces, and urban forestry, to improve stormwater management, water quality, and microclimatic regulation.
Diversifying Water Sources and Supplies
: Exploring alternative water sources, such as groundwater, desalination, or water reuse, to reduce reliance on a single, potentially vulnerable supply.
Improving Water Conservation and Efficiency
: Implementing demand-side management strategies, including leak detection, water-efficient fixtures, and incentives for water-conscious behavior.
Strengthening Monitoring and Early Warning Systems
: Enhancing the ability to detect and respond to changes in water availability, quality, and extreme events through improved data collection and real-time analysis.
By embracing these strategies and drawing on innovative planning frameworks like the one developed by the MIT researchers, water managers and community leaders can work towards building more sustainable, resilient, and adaptable water infrastructure – safeguarding their communities’ access to this vital resource in the face of a changing climate.
Conclusion: Charting a Sustainable Water Future
As the impacts of climate change continue to unfold, the need for forward-thinking, flexible water infrastructure planning has never been more pressing. The framework developed by the MIT researchers offers a valuable tool for decision-makers, empowering them to make more informed choices about the most appropriate and cost-effective approaches for their communities.
By incorporating the potential to learn about future climate conditions, this planning framework helps to overcome the limitations of traditional water infrastructure design, which has often been constrained by the assumption of persistent uncertainty. By embracing adaptive, flexible solutions, communities can position themselves to better withstand the challenges of a changing climate and secure their long-term water security.
As the world works towards the United Nations’ Sustainable Development Goal 6 – ensuring access to clean water and sanitation for all – the insights and strategies outlined in this article can serve as a roadmap for water managers, policymakers, and community leaders. By prioritizing sustainable, climate-resilient water infrastructure, we can build a future where everyone has reliable access to this essential resource, no matter the shifts in our global climate.
